Film/substrate adhesion

Concurrent bombardment during film growth affects film properties such as the film—substrate adhesion, density, surface area, porosity, surface coverage, residual film stress, index of refraction, and electrical resistivity. In reactive ion plating, the use of concurrent bombardment allows the deposition of stoichiometric, high density films of compounds such as TiN, ZrN, and Zr02 at low substrate temperatures. 

The chemical literature reveals relatively new and varied interests for nitrile elastomer-modification of epoxy resins in diverse areas of coatings and primers. Desirable properties such as impact resistance, mandrel bend and adhesion improvement are attainable with little or no sacrifice in critical film properties. In some instances, it is documented that proper elastomer modification of select epoxy coatings will enhance corrosion and moisture resistance. This may relate to better film/substrate adhesion durability. The combined literature, journal and patent, has led to continuing study of nitrile elastomer modified epoxy coatings. 

Understanding film deposition and growth Improving film/substrate adhesion Increasing reproducibility... 

Rubinstein et al. [22] used the SAM of p-aminothiophenol to increase the polyaniline (PANI) film/substrate adhesion. It became possible to calculate the film density from the mass data using the QCM and thickness data by ellipsometry. They... 

For sputtered films Sakaguchi et al. (1988) report larger thermal conductivities than for bulk samples. The mechanical properties show that the film-substrate adhesion occurs in the following order for the substrate used Ni foil > Ni > Al foil > Cu foil > Cu > Al > glass. Such an order sqjpears to be due to the difference of the thermal e ansivity at the film-substrate interface. 

In most cases, the injection molding conditions significantly affect the morphology and subsequently the bulk mechanical properties of the product. This effect is more pronounced when polymer blends or composites are used where the extent of dispersion and orientation of the disperse phases or reinforcements would affect the final property of the molding. In film insert moldings, it is important to ensure that the film is firmly attached to the substrate. Hence, the distribution of the disperse phases (Acrylonitrile-butadiene-styrene in polycarbonate) at the interface is investigated to establish correlations between phase anisotropy, film-substrate adhesion and bulk mechanical properties. 

It could be inferred that the apparent difference in film-substrate adhesion can be caused by various factors brought about by the different film thicknesses. Firstly, a thick film will decrease the overall free volume in the mold cavity for subsequent filling by the melted resin during injection molding. Since injection molding conditions were... 

Adhesion the degree of attachment between a paint or varnish film and the underlying material with which it is in contact. The latter may be another film of paint (adhesion between one coat and another) or any other material such as wood, metal, plaster, etc. (adhesion between a coat of paint and its substrate). Adhesion should not be confused with cohesion (. v.). 

Composition of Surface Film and Adhesion of UVC Lacquer. As the deadhesion of UVC lacquer has occurred at the interface between the substrate and lacquer (or in the oil film), both chromium oxide and oil film affect the adhesion performance. From this standpoint, the adhesion of the UVC lacquer is summarized in Fig. 9. When chromium oxide is hydrated to a high degree or surface oil is oxidized to a greater level, the adhesion of the UVC lacquer does not deteriorate. 

Extrusion Coating. In extrusion coating, a thin film of molten polymer is pressed onto or into the substrate. Coating thickness may range from 6.5 ua or less to more than 100 xm. In polymer lamination, a related operation, two or more substrates, such as paper or aluminum foil, are combined by using the polymer film as adhesive and moisture barrier. In order to coat a substrate, the polymer must be extruded through a narrow slit in the extrusion coating die by an extruder screw. 

General Process Considerations. To be useful, a CVD process must produce thin films with reproducible and controllable properties including purity, composition, film thickness, adhesion, crystalline structure, and surface morphology. The growth rates must be reasonable, and the deposition must not have significant impact on the microstructures already formed in the substrate. The deposition time must be sufficiently short, and the temperature has to be low enough so that dopant solid-state diffusion does not smear the results of previous processing steps. 

Fig. 2 Schematic depiction of wrinkle formation of a hard film in adhesive contact with a softer elastomeric substrate. The wavelength X is mainly determined by film thickness h and elastic properties of film and substrate. The amplitude A can be controlled by the strain...

The grit comprised particles ranging from 1 to 2 mm in diameter and the initial studies were into ways of retaining these in a layer of wet adhesive epoxide and moisture-curing polyurethane adhesives were tried. However, adhesion to the substrate was poor (it was found possible to remove easily the entire film of adhesive and grit). 

Accelerates peroxide and air-based cures (e.g., polyester SMC/BMC) adhesion promoter and primer for organic substrates Adhesion promoter for printing inks on treated polyolefin films Comparable to organosilanes at lower cost Adhesion promoters and primers for treated polyolefins... 

Models describing the mechanics of cracking and loss of adhesion occurring in uniaxially stretched film/substrate systems are numerous. 

Faupel et al. have analyzed the adhesion of metal films deposited on polymer substrates strained in an optical microscope. The deadhesion energy was deduced from the difference in the stress versus strain curves between the film/substrate system and the substrate only. 

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